| 1 | /* SEC_MERGE support. |
| 2 | Copyright 2001, 2002 Free Software Foundation, Inc. |
| 3 | Written by Jakub Jelinek <jakub@redhat.com>. |
| 4 | |
| 5 | This file is part of BFD, the Binary File Descriptor library. |
| 6 | |
| 7 | This program is free software; you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation; either version 2 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program; if not, write to the Free Software |
| 19 | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| 20 | |
| 21 | /* This file contains support for merging duplicate entities within sections, |
| 22 | as used in ELF SHF_MERGE. */ |
| 23 | |
| 24 | #include "bfd.h" |
| 25 | #include "sysdep.h" |
| 26 | #include "libbfd.h" |
| 27 | #include "hashtab.h" |
| 28 | #include "libiberty.h" |
| 29 | |
| 30 | struct sec_merge_sec_info; |
| 31 | |
| 32 | /* An entry in the section merge hash table. */ |
| 33 | |
| 34 | struct sec_merge_hash_entry |
| 35 | { |
| 36 | struct bfd_hash_entry root; |
| 37 | /* Length of this entry. */ |
| 38 | unsigned int len; |
| 39 | /* Start of this string needs to be aligned to |
| 40 | alignment octets (not 1 << align). */ |
| 41 | unsigned int alignment; |
| 42 | union |
| 43 | { |
| 44 | /* Index within the merged section. */ |
| 45 | bfd_size_type index; |
| 46 | /* Entity size (if present in suffix hash tables). */ |
| 47 | unsigned int entsize; |
| 48 | /* Entry this is a suffix of (if alignment is 0). */ |
| 49 | struct sec_merge_hash_entry *suffix; |
| 50 | } u; |
| 51 | /* Which section is it in. */ |
| 52 | struct sec_merge_sec_info *secinfo; |
| 53 | /* Next entity in the hash table. */ |
| 54 | struct sec_merge_hash_entry *next; |
| 55 | }; |
| 56 | |
| 57 | /* The section merge hash table. */ |
| 58 | |
| 59 | struct sec_merge_hash |
| 60 | { |
| 61 | struct bfd_hash_table table; |
| 62 | /* Next available index. */ |
| 63 | bfd_size_type size; |
| 64 | /* First entity in the SEC_MERGE sections of this type. */ |
| 65 | struct sec_merge_hash_entry *first; |
| 66 | /* Last entity in the SEC_MERGE sections of this type. */ |
| 67 | struct sec_merge_hash_entry *last; |
| 68 | /* Entity size. */ |
| 69 | unsigned int entsize; |
| 70 | /* Are entries fixed size or zero terminated strings? */ |
| 71 | boolean strings; |
| 72 | }; |
| 73 | |
| 74 | struct sec_merge_info |
| 75 | { |
| 76 | /* Chain of sec_merge_infos. */ |
| 77 | struct sec_merge_info *next; |
| 78 | /* Chain of sec_merge_sec_infos. */ |
| 79 | struct sec_merge_sec_info *chain; |
| 80 | /* A hash table used to hold section content. */ |
| 81 | struct sec_merge_hash *htab; |
| 82 | }; |
| 83 | |
| 84 | struct sec_merge_sec_info |
| 85 | { |
| 86 | /* Chain of sec_merge_sec_infos. */ |
| 87 | struct sec_merge_sec_info *next; |
| 88 | /* The corresponding section. */ |
| 89 | asection *sec; |
| 90 | /* Pointer to merge_info pointing to us. */ |
| 91 | PTR *psecinfo; |
| 92 | /* A hash table used to hold section content. */ |
| 93 | struct sec_merge_hash *htab; |
| 94 | /* First string in this section. */ |
| 95 | struct sec_merge_hash_entry *first; |
| 96 | /* Original section content. */ |
| 97 | unsigned char contents[1]; |
| 98 | }; |
| 99 | |
| 100 | static struct bfd_hash_entry *sec_merge_hash_newfunc |
| 101 | PARAMS ((struct bfd_hash_entry *, struct bfd_hash_table *, const char *)); |
| 102 | static struct sec_merge_hash_entry *sec_merge_hash_lookup |
| 103 | PARAMS ((struct sec_merge_hash *, const char *, unsigned int, boolean)); |
| 104 | static struct sec_merge_hash *sec_merge_init |
| 105 | PARAMS ((unsigned int, boolean)); |
| 106 | static struct sec_merge_hash_entry *sec_merge_add |
| 107 | PARAMS ((struct sec_merge_hash *, const char *, unsigned int, |
| 108 | struct sec_merge_sec_info *)); |
| 109 | static boolean sec_merge_emit |
| 110 | PARAMS ((bfd *, struct sec_merge_hash_entry *)); |
| 111 | static int cmplengthentry PARAMS ((const PTR, const PTR)); |
| 112 | static int last4_eq PARAMS ((const PTR, const PTR)); |
| 113 | static int last_eq PARAMS ((const PTR, const PTR)); |
| 114 | static boolean record_section |
| 115 | PARAMS ((struct sec_merge_info *, struct sec_merge_sec_info *)); |
| 116 | static void merge_strings PARAMS ((struct sec_merge_info *)); |
| 117 | |
| 118 | /* Routine to create an entry in a section merge hashtab. */ |
| 119 | |
| 120 | static struct bfd_hash_entry * |
| 121 | sec_merge_hash_newfunc (entry, table, string) |
| 122 | struct bfd_hash_entry *entry; |
| 123 | struct bfd_hash_table *table; |
| 124 | const char *string; |
| 125 | { |
| 126 | struct sec_merge_hash_entry *ret = (struct sec_merge_hash_entry *) entry; |
| 127 | |
| 128 | /* Allocate the structure if it has not already been allocated by a |
| 129 | subclass. */ |
| 130 | if (ret == (struct sec_merge_hash_entry *) NULL) |
| 131 | ret = ((struct sec_merge_hash_entry *) |
| 132 | bfd_hash_allocate (table, sizeof (struct sec_merge_hash_entry))); |
| 133 | if (ret == (struct sec_merge_hash_entry *) NULL) |
| 134 | return NULL; |
| 135 | |
| 136 | /* Call the allocation method of the superclass. */ |
| 137 | ret = ((struct sec_merge_hash_entry *) |
| 138 | bfd_hash_newfunc ((struct bfd_hash_entry *) ret, table, string)); |
| 139 | |
| 140 | if (ret) |
| 141 | { |
| 142 | /* Initialize the local fields. */ |
| 143 | ret->u.suffix = NULL; |
| 144 | ret->alignment = 0; |
| 145 | ret->secinfo = NULL; |
| 146 | ret->next = NULL; |
| 147 | } |
| 148 | |
| 149 | return (struct bfd_hash_entry *) ret; |
| 150 | } |
| 151 | |
| 152 | /* Look up an entry in a section merge hash table. */ |
| 153 | |
| 154 | static struct sec_merge_hash_entry * |
| 155 | sec_merge_hash_lookup (table, string, alignment, create) |
| 156 | struct sec_merge_hash *table; |
| 157 | const char *string; |
| 158 | unsigned int alignment; |
| 159 | boolean create; |
| 160 | { |
| 161 | register const unsigned char *s; |
| 162 | register unsigned long hash; |
| 163 | register unsigned int c; |
| 164 | struct sec_merge_hash_entry *hashp; |
| 165 | unsigned int len, i; |
| 166 | unsigned int index; |
| 167 | |
| 168 | hash = 0; |
| 169 | len = 0; |
| 170 | s = (const unsigned char *) string; |
| 171 | if (table->strings) |
| 172 | { |
| 173 | if (table->entsize == 1) |
| 174 | { |
| 175 | while ((c = *s++) != '\0') |
| 176 | { |
| 177 | hash += c + (c << 17); |
| 178 | hash ^= hash >> 2; |
| 179 | ++len; |
| 180 | } |
| 181 | hash += len + (len << 17); |
| 182 | } |
| 183 | else |
| 184 | { |
| 185 | for (;;) |
| 186 | { |
| 187 | for (i = 0; i < table->entsize; ++i) |
| 188 | if (s[i] != '\0') |
| 189 | break; |
| 190 | if (i == table->entsize) |
| 191 | break; |
| 192 | for (i = 0; i < table->entsize; ++i) |
| 193 | { |
| 194 | c = *s++; |
| 195 | hash += c + (c << 17); |
| 196 | hash ^= hash >> 2; |
| 197 | } |
| 198 | ++len; |
| 199 | } |
| 200 | hash += len + (len << 17); |
| 201 | len *= table->entsize; |
| 202 | } |
| 203 | hash ^= hash >> 2; |
| 204 | len += table->entsize; |
| 205 | } |
| 206 | else |
| 207 | { |
| 208 | for (i = 0; i < table->entsize; ++i) |
| 209 | { |
| 210 | c = *s++; |
| 211 | hash += c + (c << 17); |
| 212 | hash ^= hash >> 2; |
| 213 | } |
| 214 | len = table->entsize; |
| 215 | } |
| 216 | |
| 217 | index = hash % table->table.size; |
| 218 | for (hashp = (struct sec_merge_hash_entry *) table->table.table[index]; |
| 219 | hashp != (struct sec_merge_hash_entry *) NULL; |
| 220 | hashp = (struct sec_merge_hash_entry *) hashp->root.next) |
| 221 | { |
| 222 | if (hashp->root.hash == hash |
| 223 | && len == hashp->len |
| 224 | && memcmp (hashp->root.string, string, len) == 0) |
| 225 | { |
| 226 | /* If the string we found does not have at least the required |
| 227 | alignment, we need to insert another copy. */ |
| 228 | if (hashp->alignment < alignment) |
| 229 | { |
| 230 | /* Mark the less aligned copy as deleted. */ |
| 231 | hashp->len = 0; |
| 232 | hashp->alignment = 0; |
| 233 | break; |
| 234 | } |
| 235 | return hashp; |
| 236 | } |
| 237 | } |
| 238 | |
| 239 | if (! create) |
| 240 | return (struct sec_merge_hash_entry *) NULL; |
| 241 | |
| 242 | hashp = (struct sec_merge_hash_entry *) |
| 243 | sec_merge_hash_newfunc ((struct bfd_hash_entry *) NULL, |
| 244 | (struct bfd_hash_table *) table, string); |
| 245 | if (hashp == (struct sec_merge_hash_entry *) NULL) |
| 246 | return (struct sec_merge_hash_entry *) NULL; |
| 247 | hashp->root.string = string; |
| 248 | hashp->root.hash = hash; |
| 249 | hashp->len = len; |
| 250 | hashp->alignment = alignment; |
| 251 | hashp->root.next = table->table.table[index]; |
| 252 | table->table.table[index] = (struct bfd_hash_entry *) hashp; |
| 253 | |
| 254 | return hashp; |
| 255 | } |
| 256 | |
| 257 | /* Create a new hash table. */ |
| 258 | |
| 259 | static struct sec_merge_hash * |
| 260 | sec_merge_init (entsize, strings) |
| 261 | unsigned int entsize; |
| 262 | boolean strings; |
| 263 | { |
| 264 | struct sec_merge_hash *table; |
| 265 | bfd_size_type amt = sizeof (struct sec_merge_hash); |
| 266 | |
| 267 | table = (struct sec_merge_hash *) bfd_malloc (amt); |
| 268 | if (table == NULL) |
| 269 | return NULL; |
| 270 | |
| 271 | if (! bfd_hash_table_init (&table->table, sec_merge_hash_newfunc)) |
| 272 | { |
| 273 | free (table); |
| 274 | return NULL; |
| 275 | } |
| 276 | |
| 277 | table->size = 0; |
| 278 | table->first = NULL; |
| 279 | table->last = NULL; |
| 280 | table->entsize = entsize; |
| 281 | table->strings = strings; |
| 282 | |
| 283 | return table; |
| 284 | } |
| 285 | |
| 286 | /* Get the index of an entity in a hash table, adding it if it is not |
| 287 | already present. */ |
| 288 | |
| 289 | static struct sec_merge_hash_entry * |
| 290 | sec_merge_add (tab, str, alignment, secinfo) |
| 291 | struct sec_merge_hash *tab; |
| 292 | const char *str; |
| 293 | unsigned int alignment; |
| 294 | struct sec_merge_sec_info *secinfo; |
| 295 | { |
| 296 | register struct sec_merge_hash_entry *entry; |
| 297 | |
| 298 | entry = sec_merge_hash_lookup (tab, str, alignment, true); |
| 299 | if (entry == NULL) |
| 300 | return NULL; |
| 301 | |
| 302 | if (entry->secinfo == NULL) |
| 303 | { |
| 304 | tab->size++; |
| 305 | entry->secinfo = secinfo; |
| 306 | if (tab->first == NULL) |
| 307 | tab->first = entry; |
| 308 | else |
| 309 | tab->last->next = entry; |
| 310 | tab->last = entry; |
| 311 | } |
| 312 | |
| 313 | return entry; |
| 314 | } |
| 315 | |
| 316 | static boolean |
| 317 | sec_merge_emit (abfd, entry) |
| 318 | register bfd *abfd; |
| 319 | struct sec_merge_hash_entry *entry; |
| 320 | { |
| 321 | struct sec_merge_sec_info *secinfo = entry->secinfo; |
| 322 | asection *sec = secinfo->sec; |
| 323 | char *pad = ""; |
| 324 | bfd_size_type off = 0; |
| 325 | int alignment_power = bfd_get_section_alignment (abfd, sec->output_section); |
| 326 | |
| 327 | if (alignment_power) |
| 328 | pad = bfd_zmalloc ((bfd_size_type) 1 << alignment_power); |
| 329 | |
| 330 | for (; entry != NULL && entry->secinfo == secinfo; entry = entry->next) |
| 331 | { |
| 332 | register const char *str; |
| 333 | register size_t len; |
| 334 | |
| 335 | len = off & (entry->alignment - 1); |
| 336 | if (len) |
| 337 | { |
| 338 | len = entry->alignment - len; |
| 339 | if (bfd_bwrite ((PTR) pad, (bfd_size_type) len, abfd) != len) |
| 340 | break; |
| 341 | off += len; |
| 342 | } |
| 343 | |
| 344 | str = entry->root.string; |
| 345 | len = entry->len; |
| 346 | |
| 347 | if (bfd_bwrite ((PTR) str, (bfd_size_type) len, abfd) != len) |
| 348 | break; |
| 349 | |
| 350 | off += len; |
| 351 | } |
| 352 | |
| 353 | if (alignment_power) |
| 354 | free (pad); |
| 355 | |
| 356 | return entry == NULL || entry->secinfo != secinfo; |
| 357 | } |
| 358 | |
| 359 | /* This function is called for each input file from the add_symbols |
| 360 | pass of the linker. */ |
| 361 | |
| 362 | boolean |
| 363 | _bfd_merge_section (abfd, psinfo, sec, psecinfo) |
| 364 | bfd *abfd; |
| 365 | PTR *psinfo; |
| 366 | asection *sec; |
| 367 | PTR *psecinfo; |
| 368 | { |
| 369 | struct sec_merge_info *sinfo; |
| 370 | struct sec_merge_sec_info *secinfo; |
| 371 | unsigned int align; |
| 372 | bfd_size_type amt; |
| 373 | |
| 374 | if (sec->_raw_size == 0 |
| 375 | || (sec->flags & SEC_EXCLUDE) |
| 376 | || (sec->flags & SEC_MERGE) == 0 |
| 377 | || sec->entsize == 0) |
| 378 | return true; |
| 379 | |
| 380 | if ((sec->flags & SEC_RELOC) != 0) |
| 381 | { |
| 382 | /* We aren't prepared to handle relocations in merged sections. */ |
| 383 | return true; |
| 384 | } |
| 385 | |
| 386 | if (sec->output_section != NULL |
| 387 | && bfd_is_abs_section (sec->output_section)) |
| 388 | { |
| 389 | /* The section is being discarded from the link, so we should |
| 390 | just ignore it. */ |
| 391 | return true; |
| 392 | } |
| 393 | |
| 394 | align = bfd_get_section_alignment (sec->owner, sec); |
| 395 | if ((sec->entsize < (unsigned int)(1 << align) |
| 396 | && ((sec->entsize & (sec->entsize - 1)) |
| 397 | || !(sec->flags & SEC_STRINGS))) |
| 398 | || (sec->entsize > (unsigned int)(1 << align) |
| 399 | && (sec->entsize & ((1 << align) - 1)))) |
| 400 | { |
| 401 | /* Sanity check. If string character size is smaller than |
| 402 | alignment, then we require character size to be a power |
| 403 | of 2, otherwise character size must be integer multiple |
| 404 | of alignment. For non-string constants, alignment must |
| 405 | be smaller than or equal to entity size and entity size |
| 406 | must be integer multiple of alignment. */ |
| 407 | return true; |
| 408 | } |
| 409 | |
| 410 | for (sinfo = (struct sec_merge_info *) *psinfo; sinfo; sinfo = sinfo->next) |
| 411 | if ((secinfo = sinfo->chain) |
| 412 | && ! ((secinfo->sec->flags ^ sec->flags) & (SEC_MERGE | SEC_STRINGS)) |
| 413 | && secinfo->sec->entsize == sec->entsize |
| 414 | && ! strcmp (secinfo->sec->name, sec->name)) |
| 415 | break; |
| 416 | |
| 417 | if (sinfo == NULL) |
| 418 | { |
| 419 | /* Initialize the information we need to keep track of. */ |
| 420 | sinfo = (struct sec_merge_info *) |
| 421 | bfd_alloc (abfd, (bfd_size_type) sizeof (struct sec_merge_info)); |
| 422 | if (sinfo == NULL) |
| 423 | goto error_return; |
| 424 | sinfo->next = (struct sec_merge_info *) *psinfo; |
| 425 | sinfo->chain = NULL; |
| 426 | *psinfo = (PTR) sinfo; |
| 427 | sinfo->htab = |
| 428 | sec_merge_init (sec->entsize, (sec->flags & SEC_STRINGS)); |
| 429 | if (sinfo->htab == NULL) |
| 430 | goto error_return; |
| 431 | } |
| 432 | |
| 433 | /* Read the section from abfd. */ |
| 434 | |
| 435 | amt = sizeof (struct sec_merge_sec_info) + sec->_raw_size - 1; |
| 436 | *psecinfo = bfd_alloc (abfd, amt); |
| 437 | if (*psecinfo == NULL) |
| 438 | goto error_return; |
| 439 | |
| 440 | secinfo = (struct sec_merge_sec_info *)*psecinfo; |
| 441 | if (sinfo->chain) |
| 442 | { |
| 443 | secinfo->next = sinfo->chain->next; |
| 444 | sinfo->chain->next = secinfo; |
| 445 | } |
| 446 | else |
| 447 | secinfo->next = secinfo; |
| 448 | sinfo->chain = secinfo; |
| 449 | secinfo->sec = sec; |
| 450 | secinfo->psecinfo = psecinfo; |
| 451 | secinfo->htab = sinfo->htab; |
| 452 | secinfo->first = NULL; |
| 453 | |
| 454 | if (! bfd_get_section_contents (sec->owner, sec, secinfo->contents, |
| 455 | (bfd_vma) 0, sec->_raw_size)) |
| 456 | goto error_return; |
| 457 | |
| 458 | return true; |
| 459 | |
| 460 | error_return: |
| 461 | *psecinfo = NULL; |
| 462 | return false; |
| 463 | } |
| 464 | |
| 465 | /* Compare two sec_merge_hash_entry structures. This is called via qsort. */ |
| 466 | |
| 467 | static int |
| 468 | cmplengthentry (a, b) |
| 469 | const PTR a; |
| 470 | const PTR b; |
| 471 | { |
| 472 | struct sec_merge_hash_entry * A = *(struct sec_merge_hash_entry **) a; |
| 473 | struct sec_merge_hash_entry * B = *(struct sec_merge_hash_entry **) b; |
| 474 | |
| 475 | if (A->len < B->len) |
| 476 | return 1; |
| 477 | else if (A->len > B->len) |
| 478 | return -1; |
| 479 | |
| 480 | return memcmp (A->root.string, B->root.string, A->len); |
| 481 | } |
| 482 | |
| 483 | static int |
| 484 | last4_eq (a, b) |
| 485 | const PTR a; |
| 486 | const PTR b; |
| 487 | { |
| 488 | struct sec_merge_hash_entry * A = (struct sec_merge_hash_entry *) a; |
| 489 | struct sec_merge_hash_entry * B = (struct sec_merge_hash_entry *) b; |
| 490 | |
| 491 | if (memcmp (A->root.string + A->len - 5 * A->u.entsize, |
| 492 | B->root.string + B->len - 5 * A->u.entsize, |
| 493 | 4 * A->u.entsize) != 0) |
| 494 | /* This was a hashtable collision. */ |
| 495 | return 0; |
| 496 | |
| 497 | if (A->len <= B->len) |
| 498 | /* B cannot be a suffix of A unless A is equal to B, which is guaranteed |
| 499 | not to be equal by the hash table. */ |
| 500 | return 0; |
| 501 | |
| 502 | if (A->alignment < B->alignment |
| 503 | || ((A->len - B->len) & (B->alignment - 1))) |
| 504 | /* The suffix is not sufficiently aligned. */ |
| 505 | return 0; |
| 506 | |
| 507 | return memcmp (A->root.string + (A->len - B->len), |
| 508 | B->root.string, B->len - 5 * A->u.entsize) == 0; |
| 509 | } |
| 510 | |
| 511 | static int |
| 512 | last_eq (a, b) |
| 513 | const PTR a; |
| 514 | const PTR b; |
| 515 | { |
| 516 | struct sec_merge_hash_entry * A = (struct sec_merge_hash_entry *) a; |
| 517 | struct sec_merge_hash_entry * B = (struct sec_merge_hash_entry *) b; |
| 518 | |
| 519 | if (B->len >= 5 * A->u.entsize) |
| 520 | /* Longer strings are just pushed into the hash table, |
| 521 | they'll be used when looking up for very short strings. */ |
| 522 | return 0; |
| 523 | |
| 524 | if (memcmp (A->root.string + A->len - 2 * A->u.entsize, |
| 525 | B->root.string + B->len - 2 * A->u.entsize, |
| 526 | A->u.entsize) != 0) |
| 527 | /* This was a hashtable collision. */ |
| 528 | return 0; |
| 529 | |
| 530 | if (A->len <= B->len) |
| 531 | /* B cannot be a suffix of A unless A is equal to B, which is guaranteed |
| 532 | not to be equal by the hash table. */ |
| 533 | return 0; |
| 534 | |
| 535 | if (A->alignment < B->alignment |
| 536 | || ((A->len - B->len) & (B->alignment - 1))) |
| 537 | /* The suffix is not sufficiently aligned. */ |
| 538 | return 0; |
| 539 | |
| 540 | return memcmp (A->root.string + (A->len - B->len), |
| 541 | B->root.string, B->len - 2 * A->u.entsize) == 0; |
| 542 | } |
| 543 | |
| 544 | /* Record one section into the hash table. */ |
| 545 | static boolean |
| 546 | record_section (sinfo, secinfo) |
| 547 | struct sec_merge_info *sinfo; |
| 548 | struct sec_merge_sec_info *secinfo; |
| 549 | { |
| 550 | asection *sec = secinfo->sec; |
| 551 | struct sec_merge_hash_entry *entry; |
| 552 | boolean nul; |
| 553 | unsigned char *p, *end; |
| 554 | bfd_vma mask, eltalign; |
| 555 | unsigned int align, i; |
| 556 | |
| 557 | align = bfd_get_section_alignment (sec->owner, sec); |
| 558 | end = secinfo->contents + sec->_raw_size; |
| 559 | nul = false; |
| 560 | mask = ((bfd_vma) 1 << align) - 1; |
| 561 | if (sec->flags & SEC_STRINGS) |
| 562 | { |
| 563 | for (p = secinfo->contents; p < end; ) |
| 564 | { |
| 565 | eltalign = p - secinfo->contents; |
| 566 | eltalign = ((eltalign ^ (eltalign - 1)) + 1) >> 1; |
| 567 | if (!eltalign || eltalign > mask) |
| 568 | eltalign = mask + 1; |
| 569 | entry = sec_merge_add (sinfo->htab, p, (unsigned) eltalign, secinfo); |
| 570 | if (! entry) |
| 571 | goto error_return; |
| 572 | p += entry->len; |
| 573 | if (sec->entsize == 1) |
| 574 | { |
| 575 | while (p < end && *p == 0) |
| 576 | { |
| 577 | if (!nul && !((p - secinfo->contents) & mask)) |
| 578 | { |
| 579 | nul = true; |
| 580 | entry = sec_merge_add (sinfo->htab, "", |
| 581 | (unsigned) mask + 1, secinfo); |
| 582 | if (! entry) |
| 583 | goto error_return; |
| 584 | } |
| 585 | p++; |
| 586 | } |
| 587 | } |
| 588 | else |
| 589 | { |
| 590 | while (p < end) |
| 591 | { |
| 592 | for (i = 0; i < sec->entsize; i++) |
| 593 | if (p[i] != '\0') |
| 594 | break; |
| 595 | if (i != sec->entsize) |
| 596 | break; |
| 597 | if (!nul && !((p - secinfo->contents) & mask)) |
| 598 | { |
| 599 | nul = true; |
| 600 | entry = sec_merge_add (sinfo->htab, p, |
| 601 | (unsigned) mask + 1, secinfo); |
| 602 | if (! entry) |
| 603 | goto error_return; |
| 604 | } |
| 605 | p += sec->entsize; |
| 606 | } |
| 607 | } |
| 608 | } |
| 609 | } |
| 610 | else |
| 611 | { |
| 612 | for (p = secinfo->contents; p < end; p += sec->entsize) |
| 613 | { |
| 614 | entry = sec_merge_add (sinfo->htab, p, 1, secinfo); |
| 615 | if (! entry) |
| 616 | goto error_return; |
| 617 | } |
| 618 | } |
| 619 | |
| 620 | return true; |
| 621 | |
| 622 | error_return: |
| 623 | for (secinfo = sinfo->chain; secinfo; secinfo = secinfo->next) |
| 624 | *secinfo->psecinfo = NULL; |
| 625 | return false; |
| 626 | } |
| 627 | |
| 628 | /* This is a helper function for _bfd_merge_sections. It attempts to |
| 629 | merge strings matching suffixes of longer strings. */ |
| 630 | static void |
| 631 | merge_strings (sinfo) |
| 632 | struct sec_merge_info *sinfo; |
| 633 | { |
| 634 | struct sec_merge_hash_entry **array, **a, **end, *e; |
| 635 | struct sec_merge_sec_info *secinfo; |
| 636 | htab_t lasttab = NULL, last4tab = NULL; |
| 637 | bfd_size_type size, amt; |
| 638 | |
| 639 | /* Now sort the strings by length, longest first. */ |
| 640 | array = NULL; |
| 641 | amt = sinfo->htab->size * sizeof (struct sec_merge_hash_entry *); |
| 642 | array = (struct sec_merge_hash_entry **) bfd_malloc (amt); |
| 643 | if (array == NULL) |
| 644 | goto alloc_failure; |
| 645 | |
| 646 | for (e = sinfo->htab->first, a = array; e; e = e->next) |
| 647 | if (e->alignment) |
| 648 | *a++ = e; |
| 649 | |
| 650 | sinfo->htab->size = a - array; |
| 651 | |
| 652 | qsort (array, (size_t) sinfo->htab->size, |
| 653 | sizeof (struct sec_merge_hash_entry *), cmplengthentry); |
| 654 | |
| 655 | last4tab = htab_create_alloc ((size_t) sinfo->htab->size * 4, |
| 656 | NULL, last4_eq, NULL, calloc, free); |
| 657 | lasttab = htab_create_alloc ((size_t) sinfo->htab->size * 4, |
| 658 | NULL, last_eq, NULL, calloc, free); |
| 659 | if (lasttab == NULL || last4tab == NULL) |
| 660 | goto alloc_failure; |
| 661 | |
| 662 | /* Now insert the strings into hash tables (strings with last 4 characters |
| 663 | and strings with last character equal), look for longer strings which |
| 664 | we're suffix of. */ |
| 665 | for (a = array, end = array + sinfo->htab->size; a < end; a++) |
| 666 | { |
| 667 | register hashval_t hash; |
| 668 | unsigned int c; |
| 669 | unsigned int i; |
| 670 | const unsigned char *s; |
| 671 | PTR *p; |
| 672 | |
| 673 | e = *a; |
| 674 | e->u.entsize = sinfo->htab->entsize; |
| 675 | if (e->len <= e->u.entsize) |
| 676 | break; |
| 677 | if (e->len > 4 * e->u.entsize) |
| 678 | { |
| 679 | s = e->root.string + e->len - e->u.entsize; |
| 680 | hash = 0; |
| 681 | for (i = 0; i < 4 * e->u.entsize; i++) |
| 682 | { |
| 683 | c = *--s; |
| 684 | hash += c + (c << 17); |
| 685 | hash ^= hash >> 2; |
| 686 | } |
| 687 | p = htab_find_slot_with_hash (last4tab, e, hash, INSERT); |
| 688 | if (p == NULL) |
| 689 | goto alloc_failure; |
| 690 | if (*p) |
| 691 | { |
| 692 | struct sec_merge_hash_entry *ent; |
| 693 | |
| 694 | ent = (struct sec_merge_hash_entry *) *p; |
| 695 | e->u.suffix = ent; |
| 696 | e->alignment = 0; |
| 697 | continue; |
| 698 | } |
| 699 | else |
| 700 | *p = (PTR) e; |
| 701 | } |
| 702 | s = e->root.string + e->len - e->u.entsize; |
| 703 | hash = 0; |
| 704 | for (i = 0; i < e->u.entsize; i++) |
| 705 | { |
| 706 | c = *--s; |
| 707 | hash += c + (c << 17); |
| 708 | hash ^= hash >> 2; |
| 709 | } |
| 710 | p = htab_find_slot_with_hash (lasttab, e, hash, INSERT); |
| 711 | if (p == NULL) |
| 712 | goto alloc_failure; |
| 713 | if (*p) |
| 714 | { |
| 715 | struct sec_merge_hash_entry *ent; |
| 716 | |
| 717 | ent = (struct sec_merge_hash_entry *) *p; |
| 718 | e->u.suffix = ent; |
| 719 | e->alignment = 0; |
| 720 | } |
| 721 | else |
| 722 | *p = (PTR) e; |
| 723 | } |
| 724 | |
| 725 | alloc_failure: |
| 726 | if (array) |
| 727 | free (array); |
| 728 | if (lasttab) |
| 729 | htab_delete (lasttab); |
| 730 | if (last4tab) |
| 731 | htab_delete (last4tab); |
| 732 | |
| 733 | /* Now assign positions to the strings we want to keep. */ |
| 734 | size = 0; |
| 735 | secinfo = sinfo->htab->first->secinfo; |
| 736 | for (e = sinfo->htab->first; e; e = e->next) |
| 737 | { |
| 738 | if (e->secinfo != secinfo) |
| 739 | { |
| 740 | secinfo->sec->_cooked_size = size; |
| 741 | secinfo = e->secinfo; |
| 742 | } |
| 743 | if (e->alignment) |
| 744 | { |
| 745 | if (e->secinfo->first == NULL) |
| 746 | { |
| 747 | e->secinfo->first = e; |
| 748 | size = 0; |
| 749 | } |
| 750 | size = (size + e->alignment - 1) & ~((bfd_vma) e->alignment - 1); |
| 751 | e->u.index = size; |
| 752 | size += e->len; |
| 753 | } |
| 754 | } |
| 755 | secinfo->sec->_cooked_size = size; |
| 756 | |
| 757 | /* And now adjust the rest, removing them from the chain (but not hashtable) |
| 758 | at the same time. */ |
| 759 | for (a = &sinfo->htab->first, e = *a; e; e = e->next) |
| 760 | if (e->alignment) |
| 761 | a = &e->next; |
| 762 | else |
| 763 | { |
| 764 | *a = e->next; |
| 765 | if (e->len) |
| 766 | { |
| 767 | e->secinfo = e->u.suffix->secinfo; |
| 768 | e->alignment = e->u.suffix->alignment; |
| 769 | e->u.index = e->u.suffix->u.index + (e->u.suffix->len - e->len); |
| 770 | } |
| 771 | } |
| 772 | } |
| 773 | |
| 774 | /* This function is called once after all SEC_MERGE sections are registered |
| 775 | with _bfd_merge_section. */ |
| 776 | |
| 777 | boolean |
| 778 | _bfd_merge_sections (abfd, xsinfo, remove_hook) |
| 779 | bfd *abfd ATTRIBUTE_UNUSED; |
| 780 | PTR xsinfo; |
| 781 | void (*remove_hook) PARAMS((bfd *, asection *)); |
| 782 | { |
| 783 | struct sec_merge_info *sinfo; |
| 784 | |
| 785 | for (sinfo = (struct sec_merge_info *) xsinfo; sinfo; sinfo = sinfo->next) |
| 786 | { |
| 787 | struct sec_merge_sec_info * secinfo; |
| 788 | |
| 789 | if (! sinfo->chain) |
| 790 | continue; |
| 791 | |
| 792 | /* Move sinfo->chain to head of the chain, terminate it. */ |
| 793 | secinfo = sinfo->chain; |
| 794 | sinfo->chain = secinfo->next; |
| 795 | secinfo->next = NULL; |
| 796 | |
| 797 | /* Record the sections into the hash table. */ |
| 798 | for (secinfo = sinfo->chain; secinfo; secinfo = secinfo->next) |
| 799 | if (secinfo->sec->flags & SEC_EXCLUDE) |
| 800 | { |
| 801 | *secinfo->psecinfo = NULL; |
| 802 | if (remove_hook) |
| 803 | (*remove_hook) (abfd, secinfo->sec); |
| 804 | } |
| 805 | else if (! record_section (sinfo, secinfo)) |
| 806 | break; |
| 807 | |
| 808 | if (secinfo) |
| 809 | continue; |
| 810 | |
| 811 | if (sinfo->htab->first == NULL) |
| 812 | continue; |
| 813 | |
| 814 | if (sinfo->htab->strings) |
| 815 | merge_strings (sinfo); |
| 816 | else |
| 817 | { |
| 818 | struct sec_merge_hash_entry *e; |
| 819 | bfd_size_type size = 0; |
| 820 | |
| 821 | /* Things are much simpler for non-strings. |
| 822 | Just assign them slots in the section. */ |
| 823 | secinfo = NULL; |
| 824 | for (e = sinfo->htab->first; e; e = e->next) |
| 825 | { |
| 826 | if (e->secinfo->first == NULL) |
| 827 | { |
| 828 | if (secinfo) |
| 829 | secinfo->sec->_cooked_size = size; |
| 830 | e->secinfo->first = e; |
| 831 | size = 0; |
| 832 | } |
| 833 | size = (size + e->alignment - 1) |
| 834 | & ~((bfd_vma) e->alignment - 1); |
| 835 | e->u.index = size; |
| 836 | size += e->len; |
| 837 | secinfo = e->secinfo; |
| 838 | } |
| 839 | secinfo->sec->_cooked_size = size; |
| 840 | } |
| 841 | |
| 842 | /* Finally shrink all input sections which have not made it into |
| 843 | the hash table at all. */ |
| 844 | for (secinfo = sinfo->chain; secinfo; secinfo = secinfo->next) |
| 845 | if (secinfo->first == NULL) |
| 846 | { |
| 847 | secinfo->sec->_cooked_size = 0; |
| 848 | secinfo->sec->flags |= SEC_EXCLUDE; |
| 849 | } |
| 850 | } |
| 851 | |
| 852 | return true; |
| 853 | } |
| 854 | |
| 855 | /* Write out the merged section. */ |
| 856 | |
| 857 | boolean |
| 858 | _bfd_write_merged_section (output_bfd, sec, psecinfo) |
| 859 | bfd *output_bfd; |
| 860 | asection *sec; |
| 861 | PTR psecinfo; |
| 862 | { |
| 863 | struct sec_merge_sec_info *secinfo; |
| 864 | file_ptr pos; |
| 865 | |
| 866 | secinfo = (struct sec_merge_sec_info *) psecinfo; |
| 867 | |
| 868 | if (!secinfo->first) |
| 869 | return true; |
| 870 | |
| 871 | pos = sec->output_section->filepos + sec->output_offset; |
| 872 | if (bfd_seek (output_bfd, pos, SEEK_SET) != 0) |
| 873 | return false; |
| 874 | |
| 875 | if (! sec_merge_emit (output_bfd, secinfo->first)) |
| 876 | return false; |
| 877 | |
| 878 | return true; |
| 879 | } |
| 880 | |
| 881 | /* Adjust an address in the SEC_MERGE section. Given OFFSET within |
| 882 | *PSEC, this returns the new offset in the adjusted SEC_MERGE |
| 883 | section and writes the new section back into *PSEC. */ |
| 884 | |
| 885 | bfd_vma |
| 886 | _bfd_merged_section_offset (output_bfd, psec, psecinfo, offset, addend) |
| 887 | bfd *output_bfd ATTRIBUTE_UNUSED; |
| 888 | asection **psec; |
| 889 | PTR psecinfo; |
| 890 | bfd_vma offset, addend; |
| 891 | { |
| 892 | struct sec_merge_sec_info *secinfo; |
| 893 | struct sec_merge_hash_entry *entry; |
| 894 | unsigned char *p; |
| 895 | asection *sec = *psec; |
| 896 | |
| 897 | secinfo = (struct sec_merge_sec_info *) psecinfo; |
| 898 | |
| 899 | if (offset + addend >= sec->_raw_size) |
| 900 | { |
| 901 | if (offset + addend > sec->_raw_size) |
| 902 | { |
| 903 | (*_bfd_error_handler) |
| 904 | (_("%s: access beyond end of merged section (%ld + %ld)"), |
| 905 | bfd_get_filename (sec->owner), (long) offset, (long) addend); |
| 906 | } |
| 907 | return (secinfo->first ? sec->_cooked_size : 0); |
| 908 | } |
| 909 | |
| 910 | if (secinfo->htab->strings) |
| 911 | { |
| 912 | if (sec->entsize == 1) |
| 913 | { |
| 914 | p = secinfo->contents + offset + addend - 1; |
| 915 | while (p >= secinfo->contents && *p) |
| 916 | --p; |
| 917 | ++p; |
| 918 | } |
| 919 | else |
| 920 | { |
| 921 | p = secinfo->contents |
| 922 | + ((offset + addend) / sec->entsize) * sec->entsize; |
| 923 | p -= sec->entsize; |
| 924 | while (p >= secinfo->contents) |
| 925 | { |
| 926 | unsigned int i; |
| 927 | |
| 928 | for (i = 0; i < sec->entsize; ++i) |
| 929 | if (p[i] != '\0') |
| 930 | break; |
| 931 | if (i == sec->entsize) |
| 932 | break; |
| 933 | p -= sec->entsize; |
| 934 | } |
| 935 | p += sec->entsize; |
| 936 | } |
| 937 | } |
| 938 | else |
| 939 | { |
| 940 | p = secinfo->contents |
| 941 | + ((offset + addend) / sec->entsize) * sec->entsize; |
| 942 | } |
| 943 | entry = sec_merge_hash_lookup (secinfo->htab, p, 0, false); |
| 944 | if (!entry) |
| 945 | { |
| 946 | if (! secinfo->htab->strings) |
| 947 | abort (); |
| 948 | /* This should only happen if somebody points into the padding |
| 949 | after a NUL character but before next entity. */ |
| 950 | if (*p) |
| 951 | abort (); |
| 952 | if (! secinfo->htab->first) |
| 953 | abort (); |
| 954 | entry = secinfo->htab->first; |
| 955 | p = secinfo->contents |
| 956 | + ((offset + addend) / sec->entsize + 1) * sec->entsize |
| 957 | - entry->len; |
| 958 | } |
| 959 | |
| 960 | *psec = entry->secinfo->sec; |
| 961 | return entry->u.index + (secinfo->contents + offset - p); |
| 962 | } |